Rio Ferdinand concedes he was unimpressed with Nemanja Vidic after his arrival at Manchester United and predicted with Wayne Rooney that the defender would not last long at Old Trafford.

Vidic and Ferdinand eventually went on to form a superb centre-back partnership over eight-and-a-half seasons, which helped United to five Premier League crowns and Champions League glory in 2008.

But Rooney and his fellow England international had immediate doubts when Alex Ferguson signed Vidic from Spartak Moscow in January 2006.

Ferdinand told United's website: "Never heard of him. I'll be totally honest, that was my reaction when I heard that we were signing Nemanja Vidic.

"At the time we had Mikael Silvestre and Wes Brown as our other centre-halves. The manager wanted competition for places, Wes had had a few injuries and Vida was a punt to bring that extra competition. 

"Liverpool were interested as well, Aston Villa and a few others, and then he signed for us.

"I had no idea what to expect from him, no preconceptions. When someone joins the club, you're quickly sussing them out and forming opinions.

"From what I was seeing in his early training sessions, Vida was struggling, especially physically. That wasn't just strength-wise, but breathing, too. The pace of the training sessions were just such a shift in what he'd been used to. It wasn't easy for him.

"I had a conversation with Wayne Rooney – a couple of times, actually – about both Vidic and Patrice Evra, who had joined at the same time. 

"We were both basically saying, 'Wow, how have we signed these two?' Wayne was playing against Vida in training and he was quite clear on Vida's issues: he wasn't strong enough, wasn't aggressive enough, just didn't seem like a Man United player.

"I remember thinking, 'He won't be here long. No chance he's gonna be here long'. Speaking to him since, I know now that back when he first signed, he was nervous. He was wondering, 'Have I made the right move?'

"It was so difficult for him. He was playing against Wayne Rooney, Cristiano Ronaldo and Louis Saha every day. The standards expected of him had shot up massively overnight. We were judging him harshly, but he was judging himself harshly too."

Vidic improved various aspects of his game and quickly developed a close bond with Ferdinand around the United training ground as he settled into life at the club.

"He went away and worked very diligently on a lot of things," continued Ferdinand.

"He spent a lot more time in the gym, getting himself physically ready, preparing himself, conditioning himself for the right level so he could actually compete.

"Then there just came a point – I can't think of a specific day or date – when he was just competing. He just got accustomed to it over a period of time.

"The best word to describe the player Vida became is formidable. You could see strikers going up with him, thinking, 'Oh god, he's gonna smash me'. You could see fear in strikers. 

"He was someone who was horrible to play against. He'd go to head the ball and head you. Vida had the most bloody noses I've seen out of anybody I've ever played with.

"Even in his last game for United he walked off the pitch with a bloody nose and that just epitomised him! He was just fearless. He saw the ball, nothing else.

"After a season or two of playing with Vida, I knew that when I left United, I wanted to walk out of Old Trafford knowing we were considered the best partnership the club had ever had. That was something that drove me."